content: /*
   * Copyright 2017 David Karnok
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package hu.akarnokd.reactive4javaflow.impl.operators;
  
  import hu.akarnokd.reactive4javaflow.*;
  import hu.akarnokd.reactive4javaflow.errors.CompositeThrowable;
  import hu.akarnokd.reactive4javaflow.functionals.CheckedFunction;
  import hu.akarnokd.reactive4javaflow.fused.ConditionalSubscriber;
  import hu.akarnokd.reactive4javaflow.impl.SubscriptionArbiter;
  
  import java.util.Objects;
  import java.util.concurrent.Flow;
  
  public final class FolyamOnErrorResumeNext<T> extends Folyam<T> {
  
      final Folyam<T> source;
  
      final CheckedFunction<? super Throwable, ? extends Flow.Publisher<? extends T>> handler;
  
      public FolyamOnErrorResumeNext(Folyam<T> source, CheckedFunction<? super Throwable, ? extends Flow.Publisher<? extends T>> handler) {
          this.source = source;
          this.handler = handler;
      }
  
      @Override
      protected void subscribeActual(FolyamSubscriber<? super T> s) {
          if (s instanceof ConditionalSubscriber) {
              source.subscribe(new OnErrorResumeNextConditionalSubscriber<>((ConditionalSubscriber<? super T>)s, handler));
          } else {
              source.subscribe(new OnErrorResumeNextSubscriber<>(s, handler));
          }
      }
  
      static final class OnErrorResumeNextSubscriber<T> extends SubscriptionArbiter implements FolyamSubscriber<T> {
  
          final FolyamSubscriber<? super T> actual;
  
          final CheckedFunction<? super Throwable, ? extends Flow.Publisher<? extends T>> handler;
  
          long produced;
  
          boolean once;
  
          OnErrorResumeNextSubscriber(FolyamSubscriber<? super T> actual, CheckedFunction<? super Throwable, ? extends Flow.Publisher<? extends T>> handler) {
              this.actual = actual;
              this.handler = handler;
          }
  
          @Override
          public void onSubscribe(Flow.Subscription subscription) {
              arbiterReplace(subscription);
              if (!once) {
                  actual.onSubscribe(this);
              }
          }
  
          @Override
          public void onNext(T item) {
              produced++;
              actual.onNext(item);
          }
  
          @Override
          public void onError(Throwable throwable) {
              if (once) {
                  actual.onError(throwable);
                  return;
              }
              once = true;
              Flow.Publisher<? extends T> p;
  
              try {
                  p = Objects.requireNonNull(handler.apply(throwable), "The handler returned a null Flow.Publisher");
              } catch (Throwable ex) {
                  actual.onError(new CompositeThrowable(throwable, ex));
                  return;
              }
  
              long c = produced;
              if (c != 0) {
                  arbiterProduced(c);
              }
              p.subscribe(this);
          }
  
          @Override
          public void onComplete() {
              actual.onComplete();
          }
      }
  
      static final class OnErrorResumeNextConditionalSubscriber<T> extends SubscriptionArbiter implements ConditionalSubscriber<T> {
  
          final ConditionalSubscriber<? super T> actual;
  
          final CheckedFunction<? super Throwable, ? extends Flow.Publisher<? extends T>> handler;
  
          long produced;
  
          boolean once;
  
          OnErrorResumeNextConditionalSubscriber(ConditionalSubscriber<? super T> actual, CheckedFunction<? super Throwable, ? extends Flow.Publisher<? extends T>> handler) {
              this.actual = actual;
              this.handler = handler;
          }
  
          @Override
          public void onSubscribe(Flow.Subscription subscription) {
              arbiterReplace(subscription);
              if (!once) {
                  actual.onSubscribe(this);
              }
          }
  
          @Override
          public void onNext(T item) {
              produced++;
              actual.onNext(item);
          }
  
          @Override
          public boolean tryOnNext(T item) {
              if (actual.tryOnNext(item)) {
                  produced++;
                  return true;
              }
              return false;
          }
  
          @Override
          public void onError(Throwable throwable) {
              if (once) {
                  actual.onError(throwable);
                  return;
              }
              once = true;
              Flow.Publisher<? extends T> p;
  
              try {
                  p = Objects.requireNonNull(handler.apply(throwable), "The handler returned a null Flow.Publisher");
              } catch (Throwable ex) {
                  actual.onError(new CompositeThrowable(throwable, ex));
                  return;
              }
  
              long c = produced;
              if (c != 0) {
                  arbiterProduced(c);
              }
              p.subscribe(this);
          }
  
          @Override
          public void onComplete() {
              actual.onComplete();
          }
      }
  }
  